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1.
Food Chem ; 433: 137341, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37660603

RESUMO

A novel analytical method for the simultaneous gas chromatography-mass spectrometry (GC-MS) determination of methionine and selenomethionine in food samples is described. Samples were digested with methanesulfonic acid in a closed vessel without the need for reflux. A single step derivatization using triethyloxonium tetrafluoroborate was optimized for the conversion of the analytes into their ethyl derivatives, followed by their extraction with hexane and GC-MS analysis.. This derivatization approach was simpler and/or safer with respect to current methods based on alkyl chloroformate or silylating reagents and it yielded very clean chromatography. A design of experiment approach, based on an open source chemometric software, was used to optimize the experimental conditions. When analysis of a 1 mL volume of aqueous standard was performed, detection limits of 1 ng/g methionine and 10 ng/g for selenomethionine were obtained. The method was validated by analysis of a selenized yeast Certified Reference Material NRC SELM-1.


Assuntos
Metionina , Selenometionina , Selenometionina/análise , Metionina/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Sais , Racemetionina , Água , Saccharomyces cerevisiae/química
2.
Food Chem ; 433: 137299, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37660600

RESUMO

Three different methods were used to identify and analyze the flavor of fish gelatin with different ultrafine grinding time (0, 2, 4 and 8 h). The results of electronic nose showed that overall flavor of the samples changed. HS-SPME-GC-MS identified 65 volatile compounds, including 18 aldehydes, 7 ketones, 7 alkanes, 11 alcohols, 8 esters, 7 phenols, and 7 acids. HS-GC-IMS identified 46 volatile compounds, including 21 aldehydes, 5 ketones, 5 alcohols, 6 esters, 7 acids, 1 ether, and 1 amine. The particle size analysis results indicate that the size distribution decreases from 918.97-1167.16 and 1388.81-1780.40 nm to 157.63-177.37 and 285.90-344.55 nm with the increased of grinding time. The SEM analysis results indicate that the change in flavor characteristics of FG is due to the different storage and release abilities of volatile compounds in FG with different particle sizes.


Assuntos
Nariz Eletrônico , Compostos Orgânicos Voláteis , Animais , Gelatina , Microextração em Fase Sólida/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Álcoois/análise , Aldeídos/análise , Compostos Orgânicos Voláteis/análise , Cetonas/análise
3.
Food Chem ; 433: 137220, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37690132

RESUMO

The aim of this study was to investigate effects of cholesterol removal treatment (CRT) on the flavor, taste, texture, color, and nutritional value of hot gel egg yolk (EY). The off-odor, volatile components and taste of EY treated with CRT were studied by electronic nose (E-nose), gas chromatography-mass spectrometry (GC-MS) and electronic tongue (E-tongue). The effect of CRT on the nutritional value of EY was studied by amino acid and fatty acid analysis. The CRT significantly reduced the content of hexanal, 2-amyl-furan, 1-octene-3-ol, styrene and heptanal in EY1-EY4, also decreased its bitter taste without affecting other taste and elasticity. In addition, the CRT did not affect the essential amino acids (EAA) content and L*, a* and b* values of EY1-EY4, but it led to the reduction in polyunsaturated fatty acids (PUFA) content. In general, the CRT is an effective way to reduce the off-odor of EY without affecting consumer acceptance.


Assuntos
Gema de Ovo , Compostos Orgânicos Voláteis , Gema de Ovo/química , Odorantes/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Nariz Eletrônico , Paladar , Compostos Orgânicos Voláteis/análise
4.
Food Chem ; 434: 137408, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-37716147

RESUMO

Different ripeness plays a key role in the final quality and flavor of Noni products, but the variations of quality and flavor during Noni ripening are still unclear. In this study, physicochemical analysis combined with electronic nose, electronic tongue and gas chromatography-mass spectrometry (GC-MS) were used to investigate the effect of different ripeness levels on Noni fruit quality and flavor chemistry. The results showed that the optimum stage of nutrient accumulation is 7-8 ripe (7M-8M), in which especially the higher contents were 144Mg/100 g vitamin C, 11.08 g/kg polyphenols, 15.32 g/kg flavonoids and 2420Mg/kg potassium. Octanoic acid and hexanoic acid with an unfriendly odor began to decrease significantly after 8 ripe (8M), the lowest contents were 256.76 and 231.26 ng/g at 9 ripe (9M). Sour, astringent and fresh tastes are the dominant tastes of Noni fruit. Therefore, the optimum harvesting time of Noni fruit is 8M.


Assuntos
Antineoplásicos , Morinda , Frutas/química , Extratos Vegetais/química , Antineoplásicos/análise , Cromatografia Gasosa-Espectrometria de Massas
5.
Food Chem ; 434: 137277, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-37774638

RESUMO

The flavor of Pacific oyster (Crassostrea gigas) significantly changed during the depuration process. This work aimed to explore the mechanism of flavor changes during the 72 h depuration by metabolomics combined with gas chromatography-ion mobility spectrometry (GC-IMS). The metabolomics analysis indicated that carbohydrate metabolism was more affected in the early stage of depuration, including the citrate cycle, glyoxylae and dicarboxylate metabolism, etc. After 72 h depuration, it affected mainly the metabolism of global and overview maps and nucleoside metabolism, etc. The equivalent umami concentration (EUC) value was calculated and exhibited a gradual increase following a 48 h depuration. The GC-MS results revealed that the content of furans was the highest, and the content of aldehydes, ketones, and alcohols was the lowest after 48 h depuration, while the content of aldehydes, ketones, and alcohols increased after 72 h depuration. All these results suggested the depuration period was recommended to be controlled within 48 h.


Assuntos
Crassostrea , Animais , Crassostrea/metabolismo , Espectrometria de Mobilidade Iônica , Espectrometria de Massas , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cetonas/metabolismo , Aldeídos/metabolismo
6.
Talanta ; 266(Pt 2): 125027, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37597341

RESUMO

In this work, a solid-phase microextraction (SPME) method combined with two-dimensional gas chromatography coupled to mass spectrometry (GC × GC-MS) was optimized and used to assess the authenticity of pomegranate juice to prevent fraudulent practices. A divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fiber was used for the extraction of the volatiles. The critical parameters that affect the extraction process, such as the sample volume, and the extraction time were studied. The optimized protocol involved the addition of 15 mL of juice in 50 mL vial and saturation with 30% w/v NaCl.The extraction was carried out within 45 min under 1000 rpm stirring and was applied in the analysis of real juice samples to assess authenticity and detect low levels of pomegranate juice adulteration with grape and apple juice down to 1%. Commercially available pomegranate juice samples were acquired (n1 = 6) and adulterated with 1% of apple juice (n2 = 6), 1% of grape juice (n3 = 6), and a mixture of 1% apple juice and 1% grape juice (n4 = 6). Authentic pomegranate juice samples and adulterated mixtures were analyzed by SPME-GC × GC-MS. The analysis resulted in the identification of 123 volatile compounds that were further processed with chemometric tools. Principal component analysis (PCA) was employed to visualize the clustering of the samples, and a two-way orthogonal partial least squares discriminant analysis (O2PLS-DA) chemometric model was developed and successfully classified the samples to authentic pomegranate juice or adulterated with an explained total variance of 87.4%. The O2PLS-DA prediction model revealed characteristic volatile markers that could be used to detect pomegranate juice fraud.


Assuntos
Quimiometria , Punica granatum , Cromatografia Gasosa-Espectrometria de Massas , Microextração em Fase Sólida , Análise por Conglomerados
7.
J Ethnopharmacol ; 318(Pt B): 117058, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-37597675

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Salvia miltiorrhiza Bunge (Danshen) and Ligusticum chuanxiong Hort. (Chuanxiong) is the core herb pair in traditional Chinese medicines (TCMs) formulae for treating ischemic stroke. However, the synergistic effect of Danshen-Chuanxiong against anti-ischemic stroke and its compatibility mechanism remains unclear. AIM OF THE STUDY: This study aimed to uncover the compatibility mechanism of Danshen-Chuanxiong against ischemic stroke through chemical profiling, pharmacodynamics evaluation, network pharmacology and experimental validation. MATERIALS AND METHODS: Ultra-high performance liquid chromatography (UHPLC) combined with quadrupole time-of-flight tandem mass spectrometry (QTOF-MS) and UHPLC connected with tandem triple quadrupole mass spectrometry (QQQ-MS) were utilized to conduct the chemical interaction analysis. Then the synergistic effects of Danshen-Chuanxiong against ischemic stroke were comprehensively evaluated by the middle cerebral artery occlusion reperfusion (MCAO/R) mice model, zebrafish ischemic stroke model and glutamic acid-induced PC12 cells injury model. Afterwards, network pharmacology and molecular docking were applied to dissect the significant active compounds and potential mechanisms. Finally, the key target proteins were experimentally validated by Western blot. RESULTS: 83 compounds were characterized in Danshen-Chuanxiong by UHPLC-QTOF-MS analysis, and 4 compounds were tentatively identified for the first time. The quantification results (24 accurately identified compounds) in 13 proportions of Danshen-Chuanxiong revealed that Danshen significantly increased the dissolution of most phthalides (from Chuanxiong), while Chuanxiong facilitated the dissolution of most phenolic acids (from Danshen) in solution. The anti-ischemic stroke effects of Danshen-Chuanxiong were significantly better than Danshen or Chuanxiong in attenuating infarct size, reducing brain edema and neurological scores in MCAO/R mice. Also, compared with single herbs, this herb pair exerted better effects of suppressing the incidence of cerebral thrombosis in zebrafish, and increasing the cell viability of glutamic acid-induced PC12 cells. In network pharmacology, 7 effective compounds (rosmarinic acid, chlorogenic acid, salvianolic acid B, (Z)-ligustilide, ferulic acid, caffeic acid, tanshinone IIA) and 5 hub targets (AKT, TNF-α, IL-1ß, CASP3 and BCL2) as well as 4 key pathways were predicted. Western blot results showed that Danshen-Chuanxiong exert therapeutic effects mainly through decreasing the protein expressions of TNF-α, IL-1ß and Cleaved-CASP3, elevating the levels of p-AKT and BCL2. CONCLUSIONS: This work provided an integration strategy for uncovering the synergistic effects and compatibility mechanism of Danshen-Chuanxiong herb pair for treating ischemic stroke, and laid foundation for the further development and utilization of this herb pair.


Assuntos
AVC Isquêmico , Salvia miltiorrhiza , Ratos , Animais , Camundongos , Caspase 3 , Simulação de Acoplamento Molecular , Proteínas Proto-Oncogênicas c-akt , Fator de Necrose Tumoral alfa , Peixe-Zebra , Cromatografia Gasosa-Espectrometria de Massas , Glutamatos , Proteínas Proto-Oncogênicas c-bcl-2
8.
Food Chem ; 432: 137150, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37634344

RESUMO

Flavor characteristics of Shanlan rice wines with different fermentation time were analyzed. Results suggested that 3-methyl-1-butanol, phenylethyl alcohol, ethyl acetate, and diethyl succinate were the characteristic volatiles of Shanlan rice wine by using headspace solid-phase microextraction-gas chromatography-mass spectrometry-olfactometry. The most varieties (38) of volatiles appeared at a 3-year-fermentation time, contributing a unique and harmonious aroma to the Shanlan rice wine fermented for 3 years, but only 19 types were observed at 45-days and 1-year fermentation times. A similar trend was intuitively visible in the headspace-gas chromatography-ion mobility spectrometry analysis. The Shanlan rice wine fermented for 3 years had a similar taste profile to that fermented for 45 days, but with distinguishing contents of free amino acids (1352.80 mg/L and 2261.50 mg/L, respectively) and organic acids (9.58 g/L and 49.88 g/L, respectively). The Shanlan rice wine fermented for 1 year had a strong taste with more intensity of most taste attributes.


Assuntos
Microextração em Fase Sólida , Vinho , Cromatografia Gasosa-Espectrometria de Massas , Aminoácidos , Eletrônica
9.
Food Chem ; 432: 137095, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37657337

RESUMO

Currently, the effect of varieties on the flavor and stability of flaxseed milk remains unknown. Therefore, this study was conducted to investigate the effects of different varieties on the stability, sensory, and aromas of flaxseed milk. 51 volatile compounds were identified in flaxseed milk using Stir Bar Sorptive Extraction-Gas Chromatography-Olfactometry-Mass Spectrometry (SBSE-GC-O-MS). Among them, 1-octen-3-ol, 2-methoxy-4-vinylphenol, and 2,3,5-trimethylpyrazine contributed higher relative odor active values (ROAV), resulted in the fruity, roasted, sweet, and cucumber in flaxseed milk. Isovaleraldehyde (green notes) was not detected in XHZM. However, other compounds such as 1-nonanol (floral), γ-nonanolactone and γ-octanoic lactone (coconut milk) had higher concentrations, causing a better sensory evaluation. Additionally, its stability was relatively good. The orthogonal partial least-squares regression (OPLS) model and VIP values showed that eight compounds were responsible for the sensory differences from different varietals. The study provided references to selection and understanding flavor composition basis of flaxseed milk.


Assuntos
Linho , Leite , Animais , Odorantes , Cromatografia Gasosa-Espectrometria de Massas , Doces
10.
Food Chem ; 435: 137547, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37769558

RESUMO

Volatile organic compounds (VOCs) of walnut oil (WO) samples obtained from 5 ripening stages were analyzed by headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) and HS-solid phase microextraction-GC-mass spectrometry (HS-SPME-GC-MS). A total of 75 VOCs were identified in WO, of which 24 VOCs were found to be the key aroma-active compounds for WO by using odor activity values (OAVs) analysis. Based on chemometrics methods, flavor of WO samples can be characterized into three categories, i.e., early, mid-, and late stages. WO from early ripening stage had stronger green and sweet odor due to 1,8-cineole (OAV 280) and ethanol (OAV 134.5). While nonanal (OAV 181.82), (E)-2-octenol (OAV 160), and hexanal (OAV 103.78) were sources of intense fatty and oily odor in mid-ripening stage. For WO of later ripening stage, the flavor was affected by nonanal (OAV 192.28), 1-heptanol (OAV 150), heptanal (OAV 71.11) and some organic acids.


Assuntos
Juglans , Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Espectrometria de Mobilidade Iônica , Odorantes/análise , Compostos Orgânicos Voláteis/análise
11.
Food Chem ; 435: 137470, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37774626

RESUMO

The distinctive fragrance of Wuyi Rock Tea (WRT) has garnered high attention in recent years. Herein, we conducted a comprehensive comparison of the sensory attributes and odor-active compounds (OACs) between two quintessential WRTs, namely Rougui (RGT) and Shuixian (SXT). Sensory analysis revealed that RGT exhibited a more pronounced fruity aroma, while SXT had a more complex and intricate sensory profile. By using gas chromatography-olfactory mass spectrometry (GC-O-MS) and two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC-TOF-MS) analyses, 26 OACs were identified. Among them, 12 compounds with odor activity values > 1 were recognized as key OACs. Noteworthily, eight compounds, including 6-methyl-5-hepten-2-one, 2-ethyl-3,5-dimethylpyrazine, 2,3-diethyl-5-methylpyrazine, linalool, methyl salicylate, geraniol, (E)-ß-ionone, and (E)-nerolidol, were shared by both teas. The unique compounds for RGT were (E)-linalool oxide and (Z)-jasmone, while those for SXT were ß-cyclocitral and α-ionone. These findings offer valuable insights for better understanding the flavor differences between the two most important types of WRT.


Assuntos
Odorantes , Compostos Orgânicos Voláteis , Odorantes/análise , Chá/química , Compostos Orgânicos Voláteis/análise , Olfato , Cromatografia Gasosa-Espectrometria de Massas/métodos , Olfatometria/métodos
12.
Food Chem ; 435: 137643, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37801769

RESUMO

GC × GC-ToF-MS is increasingly used to analyze complex food flavors due to its high resolution and sensitivity, but few studies have used the method to identify aroma components of bread. For the first time, this study combines GC × GC-ToF-MS and multivariate statistical methods to explore the effects of L. paracasei fermentation on bread flavor characteristics. A total of 1534 volatile organic compounds were identified, of which 447 were obtained by metabolome normalization. Based on the variable importance for the projection and p values, 82 different compounds were screened in L. paracasei bread compared with yeast bread, and the total relative content was 1.52 times higher than that of yeast bread. 2-Furancarboxaldehyde, 5-methyl-, pentanoic acid, 2-hydroxy-4-methyl-, ethyl ester, pyrazine, 2,5-dimethyl- and γ-terpinene are aroma-presenting substances specific to L. paracasei bread that could be potential identification compounds. This study provides a new techno-theoretical approach for the characterization and discrimination of LAB bread flavors.


Assuntos
Saccharomyces cerevisiae , Compostos Orgânicos Voláteis , Pão/análise , Fermentação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Odorantes/análise , Compostos Orgânicos Voláteis/análise
13.
Food Chem ; 430: 137052, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37549629

RESUMO

Huangjiu was a Chinese national alcohol with a unique flavor. The key odorants in Jiujiang Fenggang Huangjiu (JJFG) and their succession regularities during aging were systematically researched by a sensomics analysis approach. The volatiles of JJFG were isolated by solvent-assisted flavor evaporation, 77 odorants were identified using gas chromatography-olfactometry-mass spectrometry combined with odor-specific magnitude estimation. Three aroma recombinants, prepared using odorants with odor activity values ≥ 1, all showed good similarities with their corresponding samples (92.1%∼97.5%). After omission/addition tests, 7 new key aroma compounds were found in JJFG, including 1-octen-3-one, 1-pentanol, guaiacol, ethyl 2-hydroxy-4-methylpentanoate, 2-phenethyl acetate, ethyl butanoate, and (E,Z)-2,6-nonadienal. Using orthogonal partial least squares-discriminant analysis, 20 compounds with VIP ≥ 1 were found to be important indicators during aging of JJFG. Among them, sotolon, 3-methylsulfanylpropanal, et al. increased with aging. The improved solid-phase extraction can effectively quantify sotolon, with a recovery rate of 80.96%∼91.75%.


Assuntos
Odorantes , Compostos Orgânicos Voláteis , Etanol/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Odorantes/análise , Olfatometria/métodos , Compostos Orgânicos Voláteis/análise
14.
J Ethnopharmacol ; 318(Pt A): 116891, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-37423518

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Although the root of Cannabis sativa L. has been mentioned in some regions, such as the Vale do São Francisco, for its potential traditional medicinal use as an anti-inflammatory, anti-asthmatic, and against gastrointestinal diseases, it has received little exploration and discussion. AIM OF THE STUDY: This study aimed to perform a chemical analysis of an aqueous extract of Cannabis sativa roots (AqECsR) and evaluate its pharmacological effects against uterine disorders, in vivo and ex vivo, in rodents. MATERIALS AND METHODS: The roots were provided by the Brazilian Federal Police, and the freeze-dried extract was used for the chemical analysis of the AqECsR by high performance liquid chromatography coupled with mass spectrometry (HPLC-MS). The sample was subsequently used in three doses for pharmacological assays (12.5, 25, and 50 mg/kg), which included the spasmolytic activity test and the primary dysmenorrhea test. The primary dysmenorrhea test aimed to verify the effect of AqECsR on induced abdominal contortions in female mice in vivo and to perform a morphometric analysis of the organs. Association tests at subtherapeutic doses of AqECsR with antidysmenorrheic drugs were also performed. RESULTS: The data obtained by HPLC-MS suggested the presence of four substances: cannabisativine, anhydrocannabisativine, feruloyltyramine, and p-coumaroyltyramine. In the pharmacological assays, the AqECsR showed no spasmolytic effect. However, in the antidysmenorrheal activity test, AqECsR demonstrated a significant in vivo effect of reducing oxytocin-induced abdominal contortions. Morphometric analysis of the uterus showed no significant organ enlargement effect, and the association of AqECsR with subtherapeutic doses of three drugs used in antidysmenorrheal therapy (mefenamic acid, scopolamine, and nifedipine) showed an effect in reducing abdominal contortions. CONCLUSIONS: In conclusion, AqECsR contains four chemical compounds and exhibits an antidysmenorrheic effect both alone and in association with drugs, reducing abdominal contortions in female mice without generating organ enlargement in the animals. Further studies are needed to prove the mechanism of action by which AqECsR promotes its effect on primary dysmenorrhea and to explore its associations.


Assuntos
Cannabis , Humanos , Feminino , Camundongos , Animais , Cannabis/química , Dismenorreia/tratamento farmacológico , Dismenorreia/induzido quimicamente , Brasil , Cromatografia Gasosa-Espectrometria de Massas , Útero , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Extratos Vegetais/análise
15.
J Ethnopharmacol ; 318(Pt B): 116947, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-37482262

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Traditionally, Coniferous plants, in particular Pinus and Cupressus species, have been used in the treatment of burns, skin infections, and immune-mediated inflammatory diseases such as psoriasis. AIM OF THE STUDY: A comparative study between essential oils (EOs) extracted from aerial parts of three coniferous plants: Pinus canariensis C.Sm. (PC), Cupressus lusitanica Mill. (CL) and Cupressus arizonica Greene (CA), cultivated in Egypt, was designed to investigate their composition and their anti-psoriasis mechanism. MATERIALS AND METHODS: The phytochemical profiles were confirmed using Gas Chromatography-Mass Spectrometry (GC-MS) method. In-vivo Imiquimod (IMQ)-induced psoriasis model was performed and EOs were applied topically and compared to mometasone cream as a standard subsequently histopathological analysis and inflammatory biomarkers were measured. RESULTS: In GC-MS analysis, Monoterpene hydrocarbons, sesquiterpene hydrocarbons and oxygenated monoterpenes were the major detected classes in the three plants, except in Pinus canariensis essential oil, oxygenated monoterpenes were absent. A significant attenuation of imiquimod-induced psoriasis symptoms after topical application of P. canariensis C.Sm., and C. lusitanica Mill. essential oils were observed by reducing the psoriasis area severity index (PASI) score, alleviating histopathological alteration, restoring the spleen index, and decreasing serum levels of interleukins 23 and 17A. Indeed, the results of Pinus canariensis essential oil is comparable to mometasone and showed no significant difference from standard treatment. On the other hand, the topical application of C. arizonica essential oil failed to alleviate imiquimod-induced psoriasis symptoms as observed in the PSAI score, the histopathological investigation, and the spleen index. CONCLUSION: The essential oils of P. canariensis C.Sm., and C. lusitanica Mill aerial parts could be promising candidates for psoriasis treatment and for further studies on inflammation-related skin diseases.


Assuntos
Cupressaceae , Cupressus , Óleos Voláteis , Pinus , Camundongos , Animais , Óleos Voláteis/farmacologia , Óleos Voláteis/uso terapêutico , Óleos Voláteis/análise , Cromatografia Gasosa-Espectrometria de Massas , Cupressus/química , Imiquimode/toxicidade , Pinus/química , Monoterpenos/análise , Componentes Aéreos da Planta/química
16.
Carbohydr Polym ; 323: 121373, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37940270

RESUMO

Carbohydrates from polysaccharides in natural thermoset Anacardiaceae polymers of Gluta usitata, Toxicodendron succedaneum and Toxicodendron vernicifluum were identified using pyrolysis-gas chromatography-mass spectrometry with in situ trimethylsilylation. Pyrolysates resulting from the pyrolytic intermolecular chain scission of the polysaccharides were used to elucidate monomeric units. Polysaccharides, dispersed in the phenolic lacasse catalysed cross-linked macromolecules, showed to be metabolised through various catabolic and anabolic routes. Galactose functionalities, abundantly present in the polysaccharides were determined to be enzymatically converted to glucose-6-phosphate, followed by conversion via glycolysis and pentose phosphate pathways. Determination of specific routes of carbohydrate modification via glycolysis and pentose phosphate pathways facilitated differentiating G. usitata, T. succedaneum and T. vernicifluum polymers, based on the carbohydrate content. It was also found that uronic type acids, present as end groups of the branched polysaccharide structure, were biochemically converted to aldonic acids. Following the pentose phosphate and glycolysis routes, carbohydrates in G. usitata and T. vernicifluum polymers showed to be further modified via shikimate and cinnamate pathways to produce phenylpropanoid compounds. Parent molecules and pyrolysis products thereof were verified using analytical standards of high purity. The mass spectra and Kovats retention indices were compiled in an AMDIS library, which can be made available on request.


Assuntos
Anacardiaceae , Polímeros , Polímeros/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Laca , Pirólise , Polissacarídeos
17.
Food Chem ; 437(Pt 2): 137911, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-37948804

RESUMO

We propose a new analytical methodology to determine seven pesticides (atrazine, chlorpyrifos, chlorfenvinphos, α-endosulfan, bromopropylate, coumaphos, and τ-fluvalinate) in royal jelly and propolis products using gas chromatography-mass spectrometry. Sample treatment, with minor modifications for propolis, consisted of a solvent extraction with a hexane and isopropanol mixture, and a further clean-up step. Meanwhile, chromatographic analysis (<25 min) was performed in a DB-5MS column under programmed temperature conditions. In all cases we validated the method in terms of selectivity, limits of detection (0.1-2.8 µg kg-1) and quantification (0.3-9.2 µg kg-1), linearity, matrix effect (<±20 %), trueness (recoveries between 93 % and 118 %), and precision (relative standard deviation < 11 %). All royal jelly liquid dietary supplements were positive for chlorfenvinphos and, in the case of one of them, for α-endosulfan; chlorfenvinphos was determined in some fresh royal jelly samples, and no pesticide residues were detected in the propolis samples analysed.


Assuntos
Clorfenvinfos , Praguicidas , Própole , Praguicidas/análise , Própole/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Clorfenvinfos/análise , Endossulfano/análise , Solventes
18.
Carbohydr Polym ; 324: 121554, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37985118

RESUMO

Daphne mezereum L., an important medicinal plant in Scandinavian folk medicine, was used to treat ailments such as diarrhea, swelling and stomach pain. A range of natural compounds have been isolated, but little attention has been given to the polysaccharides in this plant. Previous work in our group have shown that a polysaccharide enriched fraction from the bark of D. mezereum exhibited pro-inflammatory effects. To pursue this further, the aim of the present work was to isolate and characterize these polysaccharides. From the ethanol-precipitate of a water extract, one neutral (DMP-NF) and one acidic (DMP-AF) fraction was isolated by anion-exchange chromatography. GC, GC-MS and 1D- and 2D-NMR were used to characterize the polysaccharide structures. DMP-NF appeared to be a mixture of arabinan, arabinogalactan and hemicelluloses such as xyloglucan, mannan and xylan. DMP-AF contained a pectic polysaccharide mainly consisting of an unusually long homogalacturonan backbone. Enzymatic treatment by pectinase of DMP-AF yielded DMP-ED, which contained a rhamnogalacturonan-I backbone with arabinan, galactan and arabinogalactan side chains. Both DMP-NF and DMP-ED induced IFN-γ and TNF-α secretion in peripheral blood mononuclear cells (PBMCs), DMP-ED being the most potent fraction. DMP-AF was less active, which might be due to a less sterically available rhamnogalacturonan-I domain.


Assuntos
Daphne , Leucócitos Mononucleares , Ramnogalacturonanos , Polissacarídeos/farmacologia , Polissacarídeos/química , Pectinas/química , Cromatografia Gasosa-Espectrometria de Massas
19.
Bioresour Technol ; 391(Pt A): 129928, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37914051

RESUMO

The efficient valorization of biomass for energy-derived biocrudes is essential for effective waste management. However, the production of biocrudes with high energy and reduced oxygen contents during the liquefaction process requires further insight. Therefore, the impact of reaction temperature, residence time, and ethanol: acetone on the energy compositions and bioproduct's yield enhancement were investigated. The biocrudes obtained were characterized using elemental analysis, GC-MS, FTIR, GPC and TGA to understand the effects of process parameters on the biocrudes' compositions. An improved HHV (38.18 MJ/kg) and lower O/C ratio (0.11) were obtained at 430 °C, 35 min and 50% ethanol with a significant improvement in the enhancement factor, deoxygenation, and percentage hydrogenation of 2.63, 36.88%, and 77.87%, respectively. The presence of ketones, hydrocarbons, phenolics and aromatics of 23.74, 4.28, 37.20 and 17.81% respectively indicate the potential of the obtained biocrude as renewable energy sources upon further upgrading.


Assuntos
Citrus sinensis , Temperatura , Etanol , Biomassa , Cromatografia Gasosa-Espectrometria de Massas , Biocombustíveis , Água
20.
Food Chem ; 437(Pt 1): 137904, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-37926030

RESUMO

The release mechanism of flavor during caviar storage was studied by the interaction between phosvitin and four aldehydes. Gas chromatography-mass spectrometry showed that the binding rate of phosvitin with 3-methylbutanal, nonanal, (E,Z)-2,6-nonadienal, and (E)-2-octenal decreased with an increase in the aldehyde concentrations. Among them, (E,Z)-2,6-Nonadienal (0.5 mM) had the highest binding rate (84.47%). The main quenching mechanism of (E,Z)-2,6-nonadienal with phosvitin was static quenching and the binding force comprised spontaneous hydrophobic interactions. An increase in the aldehyde concentrations reduced the α-helix content of phosvitin and led to aggregation of the microstructure of phosvitin. The results of molecular docking showed that tyr residue contributed the most to the binding of phosvitin to aldehydes. This study has elucidated the mechanism of the effect of caviar protein on changes in the caviar flavor during storage and provides effective strategies for regulation of caviar flavor during storage.


Assuntos
Aldeídos , Fosvitina , Animais , Simulação de Acoplamento Molecular , Aldeídos/análise , Cromatografia Gasosa-Espectrometria de Massas , Peixes , Fatores de Transcrição
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